Which of the following statements about solid friction is...
Which of the following statements about solid friction is/are correct?
I. Friction depends on the nature of the surfaces in contact
II. Friction depends on the area of contact
III. Friction always acts in the direction of motion.
I only
II only
III only
I and II only
I, II and III
Correct answer is A
No explanation has been provided for this answer.
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